Using lights in daytime (and rear light mod.)

S.Giles

Guest
Hello,

Now that I finally have some decent lights ('Cree' front light with Li ion rechargeable batteries), I've adopted the policy of always having them switched on whether it's day or night time. It just doesn't seem worth not having them on, since any possibility of being even a little more visible to vehicle drivers is worth having, and the batteries are easily recharged so there's little hassle and no expense involved. This particularly applies at this time of year, when the sun is low in the sky and casts long shadows.

Also (being handy with a soldering iron), I've adapted my rear light from taking two AAA batteries to using an external battery pack (actually an old 18650 Li ion cell which I had spare). The cell is pushed inside one of those spongy handlebar grips which is then tucked up underneath the saddle, and connected to the light unit with a short wire and standard 2.5mm connector. This is a good solution, since the light now runs at 3.7-4.2v instead of 3.0v so it's BRIGHT. The project took me about 30 minutes to do, was interesting, and cost very little. I was initially concerned that the added voltage would damage the LED's, but a couple of weeks in and everything is working just fine. The battery lasts for several weeks (being used about 45 minutes/day) between charges.

There is one downside to keeping the lights on during the day, though, and that is people 'helpfully' shouting out 'Hey, do you know your lights are on?', which seems to happen on a regular basis. At least this confirms that the lights are visible in daylight and therefore justifies them being switched on in the first place!

All-in-all, I feel safer with much brighter lights on my bike (be it day or night), which is an advantage worth having in itself.

Steve
 
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Shortmember

Bickerton Cyclocross Racing Team groupie
Visibility wise, I think a hi-viz jacket has the same effect, but uses a lot less battery power during daylight hours.
 
OP
S.Giles

S.Giles

Guest
Visibility wise, I think a hi-viz jacket has the same effect, but uses a lot less battery power during daylight hours.
Agreed, with the caveat that high-viz jackets work best when they are reflecting light shone directly at them, which tends not to happen during the day. How about using both high-viz clothing and lights, since one doesn't exclude the other?

See my remarks regarding ease of battery recharging.

Steve
 

BrynCP

Über Member
Location
Hull
Hi-Viz is twofold, the light colour to distinguish you from your surroundings, which may work during the day, and the reflective strips which may help you be seen in the dark should a light source be shining on them.

I think lights in the daytime work for Motorbikes, as they're powerful enough to be seen from a distance compared to the profile of an approaching bike.

Daylight lights on cars and cycles I don't believe offer any benefit. Daylight lights on cars only serve to make cars without them less visible and I think most bike lights give off insufficient light to be seen at any distance in the light.
 
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S.Giles

S.Giles

Guest
Out of interest, is the modded rear light still waterproof...my rear gets a full on soaking (no guards) and I wonder if a trailing wire would allow that water to knacker the light.
It's actually more waterproof than the standard unit. Because there are no batteries inside the unit itself, it never has to be opened, so I wrapped waterproof tape around to cover the joint between the two moulded plastic halves. The cable was purchased from an Ebay vendor for about £1.50, and includes waterproof shrouds around the connectors. I was careful not to make the hole too big where the cable enters the light unit. The battery itself is wrapped in gaffer tape before being pushed inside the sponge handlebar grip.

Steve
 

jonny jeez

Legendary Member
It's actually more waterproof than the standard unit. Because there are no batteries inside the unit itself, it never has to be opened, so I wrapped waterproof tape around to cover the joint between the two moulded plastic halves. The cable was purchased from an Ebay vendor for about £1.50, and includes waterproof shrouds around the connectors. I was careful not to make the hole too big where the cable enters the light unit. The battery itself is wrapped in gaffer tape before being pushed inside the sponge handlebar grip.

Steve
Cool
 
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S.Giles

S.Giles

Guest
BTW, using a 18650 battery for the rear light modification (as I did) could be considered overkill. A battery from an old Nokia phone will give many hours of use between charges, especially if the light is used in flashing mode. Nokia (thoughtfully:-) use gold contacts on their mobile phone batteries, making them easy to solder to. They also mark them with a + and - to differentiate the positive and negative terminals (ignore the middle terminal).

Nokia phones using this kind of (top quality, one assumes) Li-ion battery cost £5 in Asda.

Steve
 
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S.Giles

S.Giles

Guest
But no more visible than they once were! If drivers begin to look for lights, instead of moving objects, who's first coming out with lights on pedestrians.
It's a lights arms-race. Maybe if all lights were banned, vehicles would have to move so slowly that accidents would never happen.
 

Drago

Flouncing Nobber
Location
Poshshire
I think lights in the daytime work for Motorbikes, as they're powerful enough to be seen from a distance compared to the profile of an approaching bike.

Daylight lights on cars and cycles I don't believe offer any benefit. Daylight lights on cars only serve to make cars without them less visible and I think most bike lights give off insufficient light to be seen at any distance in the light.
They don't work on motorbikes. Research has deomstrated that only a low wattage or dim-dip system should be used, as even running the normal dip beam in daylight breaks up the visible silhouette of the vehicle, which deprives an observers brain of the visible datum required to calculate its speed.

Theres no evidence to reasonably demonstrate that it works on cars in good daylight either. The only countries where stats have shown a benefit are the ones tucked up by the arctic circle that have gloomy winter days with poor daylight.

However, the EU law makers have typically ignored anything like actual scientific data and imposed them on the basis that they must surely be good for safety, right? About as well proven as the life saving properties of cycle helmets.
 
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